First, I thought a Canon G1 X Mark II with Canon's own underwater housing would be a good idea. On the other hand Canon's G3 X actually better fits to me needs in general, but I Canon doesn't offer an underwater housing for it. So I'd have to buy a more expensive one from a third party manufacturer.

Any recommendations about the Canon G3 X and for a third party underwater housing?

And, in general, does/did anybody use this camera for underwater shots? Can/would you recommend it?

Or would a Canon G1 X or a Sony RX 100 V be the better choice? For both of them there are underwater housing available from the camera manufacturer which are not so expensive then third party ones.